TERTIARY VERTEERATA OE THE FAYt'M. 
29l> 
In tills sjiccies the anterior lobe of the plastron is longer compared with tlie 
])osterior lobe than in F. antUpia, and the outline of the shell is more regularly oval 
than in that species. Its probable identity with P. blancl'etiltorni, Reinach, is referred 
to below. In P. (vyijittiaca from the Lower Miocene of Mogara, the lobes of the 
plastron are longer in proportion to their width and the form of the vertebral shields 
is different. 
Form. & Log. — Fluvio-marine beds (Upper Eocene) : north of Birket-el-Qurnn. 
Remains of small Podocnemid tortoises are fairly numerous in the Upper Eocene 
beds, the anterior part of the plastron, for some reason or other, being most eommonly 
found. One of these was made the type of the present sjiecies Foilocnemis fajumensis, 
while others have been described by Reinach under the names P. llanckenhorni and 
P. hlanckenltorni var. ovata, the chief differences between the two species lying in 
tlie form of the suture between the epiplastrals and hyoplastrals and of the groove 
Text-fig. 93. 
Anterior portion of plastron of Podocnemis fajumensis (type specimen). 
Ent., eutoplastral bone; Ep., epiplastral bone; <■/., gular shield; lEj-p., byoplastral bone; L/., intergular 
shield ; Ms.p., mesoplastral bone ; n., humeral shield; p., pectoral shield, -j nat. size. 
(From the Ann. & Alag. Nat. Hist. [7] vol. xi.) 
between the humeral and pectoral shields. Several other specimens have been 
examined, and it is found that a considerable degree of individual variation exists 
in this respect, so that it is not impossible that the different forms described may 
be merely variants of one species, although further more satisfactory material will be 
necessary to settle this point. 
In the type specimen (text-fig. 93) the anterior border is rounded, with slight notches 
marking the boundaries of the areas covered by the epi(h'rmal shields. 'I'lie anterior 
lobe widens gently towards the bridge. The eutoplastral is diamond-shaped, all the 
sides being nearly straight. The suture between the e[)i- and hyoplastrals runs a little 
backwards from the outer angle of the eutoplastral, then forwards and outwards 
jiarallcl with the liumero-])Cctoral groove, which is about I'd cm. iii front of it. The 
intergular is small, the gulars longer, meeting in the middle line for about 1 cm. 
The humerals extend back to about the middle of the eutoplastral bone (text-fig. 93). 
